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Transistor

This is probably the hardest of the basic electronic components to understand.

But don’t worry, it’s not that hard.

A simple way is to look at the transistor as a switch controlled by an electrical signal.

If you put about 0.7 volts between the base and the emitter, you turn it on.

Note that this is true for NPN transistors. There are also other types, but worry about these later.

But, instead of having just two states (ON or OFF), it can also be “a bit on” by controlling the current that goes through its base.

A bit of current on the base produces a current of maybe 100 times more (depending on the transistor) through the Collector and Emitter. We can use this effect to build amplifiers.